Frank Says That If You Release the String When Swinging

question 30

Multiple Choice

Frank says that if you release the string when swinging a ball in a horizontal circle, the ball flies out in the radial direction defined by the string at the instant you release the ball. John says that it flies out along a tangent line perpendicular to the string, and that it then drops straight down to the ground. Which one, if either, is correct?

• A) Frank, because the centrifugal force is no longer counteracted by the string.
• B) Frank, because balls naturally fly straight out.
• C) John, because there is no centrifugal force.
• D) John, because balls fall straight down when released.
• E) Neither, because although there is no centrifugal force, and the ball's velocity is tangent to the circle at the instant of release, the ball then follows a parabolic trajectory.

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Definitions:

First Law of Thermodynamics

This principle states that energy cannot be created or destroyed, only transformed from one form to another, implying that the total energy in an isolated system remains constant.

Concentrated Energy

Energy that is intensified or focused within a small area or volume, often for the purpose of efficient transmission or usage.

Usable Energy

Energy in a form that can be directly applied to perform work or be processed into a form suitable for human needs, such as electricity or mechanical power.

Energy Transformation

The process of converting energy from one form to another, such as kinetic energy to electrical energy, fundamental to various natural phenomena and technologies.